Permaset Aqua Retarder acts as an agent to lengthen open screen time for all Permaset Aqua inks. Permaset Aqua is a waterbase ink. It's 100% solvent free, environmentally friendly formula that provides intense pigments rich in coverage with exceptional color yield. The resilient resin base is at once both soft and incredibly strong, holding up beautifully to even the most severe rub and wash tests.